However, using the "shotgun" approach by treating everyone with prophylactic anticoagulation
may not be cost-effective, and could potentially lead to complications from therapy.
Prophylactic anticoagulation was defined as unmonitored vitamin K antagonist use (1 mg daily of warfarin) for the duration of PICC use.
Specifically, to our knowledge, our study is the first to show that patients receiving current treatment for cancer are at increased risk for PICC-associated DVT and that this risk is not reduced by the use of commonly used prophylactic anticoagulation.
Although several studies in patients with malignancy and nonperipherally inserted central venous catheters suggest that prophylactic anticoagulation with low-dose warfarin may reduce the incidence of DVT, (14,15) a more recent prospective trial of low-dose (1 mg) unmonitored warfarin therapy performed by Heaton and colleagues showed no reduction in the risk of thrombosis in cancer patients with central venous catheters.
The lack of benefit of one prophylactic anticoagulation regimen (1 mg a day of unmonitored warfarin) in this patient cohort may be related to the nature of the peripheral catheter.
Our investigation suggests that one commonly used prophylactic anticoagulation regimen in these higher risk patients may not be effective.